In his chemistry class, William took 4 quizzes. His scores were 79, 78, 87, and 88. What was his average score on the quizzes?
Solution: The average is the sum of his scores divided by the number of scores. There are 4 scores and their sum is $79 + 78 + 87 + 88 = 332$ His average score is $332 \div 4 = 83$.